Pipeline failure and maintenance-16

Release time:

2024-05-09

What are the methods of steel pipe storage protection?

A: pipeline transportation is an economic and safe way of oil and gas transportation. The total length of the world's pipelines has exceeded 2.8 million km, and the annual growth rate is about 50000 km. According to relevant forecasts, the world's oil and gas demand will increase by 40% and 60% respectively in the next 20 years. In 2011-2015, the global planned and under construction pipelines exceeded 200000 km, and the total length of the pipelines increased by 11% compared with the previous five years. At present, China's pipeline industry is in a new stage of development. By the end of 2010, the total mileage of oil and gas pipelines in China has reached 68000 km, and it is expected to reach 200000 km in 2020. In the next 10 years, China's pipeline industry will have a great development.

In pipeline construction, due to project suspension, construction surplus, project standby and other factors, some steel pipes will be stored on site or in material storage for a long time, among which large-diameter steel pipes are often stored in the open air. Generally, the steel pipes stored in the open air will not have major problems in a short period of time (2-3 months), but if the open storage time is long, there will be various quality problems such as corrosion pit, wall thickness thinning after corrosion, edge warping of anti-corrosion layer, aging of anti-corrosion layer, etc., resulting in degraded use of steel pipes, waste judgment or re treatment, resulting in waste of resources.

At present, when the steel pipes are stored in the open air for a long time in China, there are some problems, such as no covering, no ideal covering protection, no supporting and too many stacking layers, etc., which lead to the corrosion of the steel pipe surface, pockmarks, wall thickness and roundness out of tolerance, aging of the anti-corrosion coating, edge warping, etc. In order to avoid all kinds of problems caused by long-term storage of steel pipes, the following suggestions are provided for the reference of production unit, storage unit and construction unit.

1) No matter bare pipe or anti-corrosion pipe, if it needs to be stored for a long time, the opaque cover shall be used for protection from the beginning of storage to avoid corrosion of steel pipe, aging of anti-corrosion coating, over edge and other phenomena.

2) The cover shall be strong and durable to prevent rot and leakage caused by long-term sun and rain.

3) When the steel pipe is covered, the surface of the steel pipe shall be ventilated to prevent the water vapor from volatilizing and gathering on the surface.

4) Steel pipes shall be stored with supports and a certain distance from the ground to ensure the ventilation of steel pipes.

5) After the steel pipes are stacked and stored, the pipe end protectors shall be removed to prevent the water from gathering at the contact surface between the pipe end protectors and the steel pipes and being difficult to volatilize.

6) During the storage of steel pipes, attention shall be paid to the stacking layers of steel pipes to avoid local stress at the pipe ends caused by too many layers, thus causing radial plastic deformation of steel pipes and damage of anti-corrosion coating.